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Image Compressor

Shrink JPG, PNG and WebP images in your browser — set the quality, cap the size, see the saving before you download.

75

75 is the usual sweet spot. Below about 50 the edges in the picture start to smear.

Output format

Longest edge

Resizing saves far more than quality does. 1920px is plenty for a full-screen web image; 1280px is plenty for a blog post.

Runs entirely in your browser · your images are never uploaded

Image Compressor — Nothing Uploaded, Because Nothing Needs to Be

Compressing an image is three operations: decode it, optionally draw it smaller, and encode it again. Every one of those happens in the browser you are reading this in. Your pictures are not sent anywhere, because there is nothing a server could do here that your own device cannot — which is the part worth knowing before you put a photo of your passport into the first result on a search page.

Two settings do the work, and one of them matters far more than the other. Quality controls how much detail the encoder is allowed to throw away; 75 is the usual sweet spot, and below about 50 you start seeing smeared edges and blocks around text. Longest edge resizes the picture, and this is where the real saving lives. A 4000-pixel-wide phone photo displayed in a 900-pixel column is carrying about five times more pixels than any screen will use. Capping the longest edge at 1920px is plenty for a full-screen web image and 1280px is plenty for a blog post, and either will beat any amount of quality tuning at the original size.

Format is the third lever, and it comes with a caveat most compression pages leave out. WebP usually wins on photographs — Google's published measurements put it 25 to 34% smaller than JPEG at matched visual quality — and unlike JPEG it keeps transparency, which makes it the sensible default for the web. But the quality numbers are not comparable across formats: 75 in a JPEG encoder and 75 in a WebP encoder are different operating points, so a like-for-like slider setting is not a like-for-like comparison. Browser encoders are also not the best encoders, and on some images, particularly flat graphics and noisy ones, the browser's WebP comes out larger than its JPEG. Switching between the two buttons costs nothing and reads the real answer off your own image, which is worth more than any rule of thumb. JPEG remains the safe choice for a file you are sending to someone, since everything on earth opens it. PNG is lossless, which means the quality slider does nothing at all — the only saving available for a PNG is the resize, and if you are compressing a photograph that was saved as a PNG, converting it to JPEG or WebP is the single biggest win on this page.

Some honest limits. Re-encoding can make a file bigger rather than smaller: an already-optimised JPEG pushed back through a browser encoder at high quality often grows, because whatever produced it made better choices than the browser will. When that happens the file is marked "none" and you are offered the original instead of a worse copy dressed up as a saving. And JPEG has no transparency, so a cut-out logo converted to JPEG gets a white background — images that actually contain transparent pixels are detected and flagged rather than quietly flattened.

One side effect is worth calling out because people usually want it: re-encoding drops every piece of metadata. EXIF, camera model, timestamps, and the GPS coordinates that phone cameras attach by default all disappear, because a canvas re-encode writes pixels and nothing else. If you are posting a photo taken at home, that matters more than the kilobytes.

The tool takes up to 20 images at once, shows the before and after for each, and lets you compare the compressed version against the original at full size before committing. Drag the quality slider and the preview follows it, which is the only reliable way to pick a number: the right quality for a screenshot of text and the right quality for a beach photo are not the same, and no default knows which one you have.

How to use the Image Compressor

  1. Drop images onto the panel, or click it to pick files. They stay on your device.
  2. Set the quality — 75 is a good starting point for photos, higher for screenshots and text.
  3. Cap the longest edge if the image is bigger than it needs to be. This saves more than quality does.
  4. Choose WebP for the web, JPEG to send to someone, or leave it on "same as input".
  5. Use "Compare with original" to check the result at full size before you keep it.
  6. Download each file, or "Download all" for the whole batch.

Questions

Are my images uploaded anywhere?

No. The file is decoded, drawn and re-encoded by your own browser, and nothing about it leaves the page — you can turn off your connection after the page loads and it still works. That is also why there is no limit on how many times you can use it.

Which format should I choose?

Try WebP first for anything going on a website: on photographs it is usually the smallest, and it keeps transparency. Then check the size against JPEG, because a quality of 75 does not mean the same thing to two different encoders and on flat or noisy images the browser's JPEG sometimes wins — switching the format button re-encodes instantly, so you can read the answer off your own file. Use JPEG for anything you are sending to someone else, and PNG only when you need lossless, where the quality slider has no effect.

How do I compress without losing quality?

Strictly, you cannot: JPEG and WebP are lossy formats, so there is always some loss. What you can do is lose nothing visible — resize the image to the size it will actually be displayed at, then use quality 80–85. That combination is usually indistinguishable from the original at normal viewing size while being a fraction of the file.

Why did my file get bigger instead of smaller?

Because it was already well compressed. Encoders differ, and a JPEG produced by a good one can grow when a browser re-encodes it at high quality. The tool notices, marks that row "none" and offers you the original file instead. Lowering the quality or capping the longest edge will produce a genuine saving.

What happened to my transparent background?

JPEG cannot store transparency, so transparent areas are filled with white. Choose WebP or PNG to keep them. Images that genuinely contain transparent pixels are flagged when this is about to happen.

Does it remove EXIF and location data?

Yes, as a side effect of re-encoding. The output contains pixels only — no camera model, no timestamp, and no GPS coordinates. If you want to strip location data from a photo before posting it, running it through here does that.

Is there a file size or file count limit?

Twenty images at a time, each up to 30 MB. Those are limits on what one browser tab can comfortably hold in memory, not licensing limits — clear the list and drop another twenty in.